The present invention generally relates to balanced transmission cable connectors, and, more particularly, to a balanced transmission cable connector to be applied to a balanced transmission cable having a small number of electric wire pairs.
There are two types of data transmission methods. One is a normal transmission method utilizing one electric wire for each set of data, and the other one is a balanced transmission method utilizing a pair of electric wires for each set of data. By the balanced transmission method, a positive signal and a negative signal, which has the same size as the positive signal but is directed in the opposite direction from the positive signal, are transmitted at the same time. Compared with the normal transmission method, the balanced transmission method is advantageous in not easily being adversely influenced by noise, and is being more widely employed. A balanced transmission cable connector is used to form a path for performing balanced transmission of data between two apparatuses. Such a balanced transmission cable connector has a structure in which a shielded connector is attached to the end of a balanced transmission cable.
Since the amount of data to be transmitted between a computer and a server is very large, a balanced transmission cable connector that connects the computer and the server is large-sized and is connected to the end of a thick balanced transmission cable that has ten or more electric wire pairs. This connector includes a lock mechanism for securing the connector to a socket of a computer and maintaining the connection of the connector to the socket, and a lock release mechanism for releasing the lock when the connector is pulled out of the socket.
In recent years, balanced transmission has been employed for apparatuses such as digital copying machines with which only a small amount of data is involved. Along with this trend, there is an increasing demand for balanced transmission cable connectors that can be used to connect such apparatuses.
In a case of employing a balanced transmission cable connector to be used in an apparatus with which only a small amount of data transmission is involved, the socket provided on the apparatus needs to be small-sized, there should be only a few of electric wire pairs, and the connector main body including the lock mechanism and the lock release mechanism should be smaller in size than a conventional one.
FIGS. 1 and 2 illustrate a conventional balanced transmission cable connector 10 that is used to connect a computer and a server. In FIGS. 1 and 2, the directions X1-X2, Y1-Y2, and Z1-Z2 represent the width direction, the longitudinal direction, and the height direction, respectively, of the balanced transmission cable connector 10. The Y1 side is the back side, and the Y2 side is the front side. In the balanced transmission cable connector 10, a contact assembly 11 and an end of a balanced transmission cable 12 are covered with a shield cover 15 that is formed by combining die-cast half shield covers 13 and 14. In FIGS. 1 and 2, the half shield cover 13 is located above the half shield cover 14. Lock members 16 and 17 are provided on two side portions aligned in the width direction of the cable connector 10, and are located outside the shield cover 15. A pull tab 18 having a lock releasing function is provided on the side of the shield cover 15 from which the balanced transmission cable 12 extends.
The conventional transmission cable connector 10 cannot be made small in size, because the lock members 16 and 17 are located outside the shield cover 15 and are provided on the two side portions of the cable connector 10 aligned in the width direction, the pull tab 18 with the lock releasing function is located on the side of the shield cover 15 from which the balanced transmission cable 12 extends, and the half shield covers 13 and 14 are made of a die-cast material.